Coke quenching liquids



COKE QUENCHING LIQUIDS Irvin A. (Ilausen, Pittsburgh, Pa, assignor to National Aluminate Corporation, Chicago, llll., a corporation of Delaware No Drawing. Application August 17, 1956 Serial No. 604,611

22 Claims. (Cl. 20237) The present invention is concerned with a process whereby coke quenching operations are rendered noncorrosive to ferrous metals. More particularly it is directed to chemically treated aqueous liquids useful in coke quenching operations.

In the production of coke from coal and other carbonaceous materials it is necessary to rapidly cool the freshly produced product to avoid spontaneous ignition. This cooling operation, known as quenching, is usually accomplished by spraying large volumes of aqueous coolant onto the hot coke.

A typical commercial quenching operation begins as the hot coke, the temperature of which ranges from about 1,000 to about 2,000 F., is transferred from the coking ovens to a coke quench car. The car is then moved to a large steel tower containing a plurality of sprays which douse aqueous liquids down onto the coke. Due to the high temperatures involved and the large volumes of vapors produced, the quench cars and towers are subjected to severe corrosive attack.

The corrosiveness of the coke quenching operation is often aggravated by the use of poor quality water as the quench liquid. In addition to the use of poor quality water it is the practice of some plants to collect the used quench water and recycle it in the operation.

Typical quench waters are usually derived from streams, rivers, sewage and the like and are blended with coke byproduct processing waters which contain large amounts of ammonia, phenolic constituents, hydrogen sulfide, tars, and minor amounts of hydrocarbon gases. Such waters are innately corrosive and when used as quench liquids their corrosive tendencies are multiplied. It would be a valuable contribution to the art if such waters could be treated with minor amounts of chemicals whereby their corrosiveness would be reduced.

It is therefore an object of the invention to provide a method of rendering coke quenching operations substantially non-corrosive to ferrous metals.

Another object is to furnish chemically treated aqueous liquids useful in coke quenching operations.

A further object is to provide a chemical corrosion inhibitor for aqueous coke quenching liquids which when used in minor amounts will reduce the corrosive tendencies of such liquids even though they may contain amounts of ammonia, hydrogen sulfide, tars, phenolic bodies and the like. Other objects will appear hereinafter.

In accordance with the invention it has been found that coke quenching operations may be rendered substantially non-corrosive to ferrous metals by using as a coke quenching vehicle an aqueous liquid containing minor, but yet corrosion inhibiting amounts, of a 1,2- substituted imidazoline containing at least one aliphatic group of at least6 carbon atoms is chain length. Quench cars and towers may be protected against corrosive attack by treating the aqueous quench liquids with as little as 2 parts per million of the chemicals of the invention. in a preferred embodiment 5 to parts per million 2,835,817 Patented Dec. 23, 1958 may be employed and under severely corrosive conditions as much as several hundred parts per million may be necessary to achieve optimum results. Usually, 5 to 10 parts per million are more than adequate and will give good results.

In conducting experiments with the inhibitors of the invention under actual coke quenching conditions it was discovered they placed upon the quench cars and towers a thick protective film that was so etfective in preventing corrosive weight loss that test specimens often gained in weight even after prolonged periods of time with only a few parts per million of treatment being present in the quench water. This film forming characteristic was more evident when the water treated contained reactive chemicals such as ammonia, phenolic liquids and reactive sulfur compounds such as hydrogen sulfide, carbon disulfide and the like.

THE 1,2-SUBSTITUTED IMIDAZOLINES The 1,2-substituted imidazolines useful in treating aqueous coke quenching liquids are heterocyclic, nitrogen containing compounds of the following general formulae:

wherein D represents a divalent, non-amino, organic radical containing less than 25 carbon atoms, composed of elements from the group consisting of C, H, O and N; D represents a divalent organic radical containing less than 25 carbon atoms, composed of elements from the group consisting of C, H, O and N, containing at least one amino group; Y and Z are from the group consisting of hydrogen and lower aliphatic groups containing not more than 6 carbon atoms; R is a member of the class consisting of hydrogen, aliphatic and cycloaliphatic hydrocarbon radicals, with the proviso that at least one occurrence of R contains 6 to 32 carbon atoms. In a preferred embodiment it is desirable to employ 1,2-substituted irnidazolines of the formula:

wherein R is a higher aliphatic group containing at least 11 carbon atoms and R, Y and Z are from the group consisting of hydrogen and lower aliphatic groups containing not more than 6 carbon atoms.

Specific, preferred species of Formula IV above have the structure:

wherein R' is a higher aliphatic group containing at least 11 carbon atoms and-'x is a small whole number not greater than 3.

In some of the formulae above described a substituent on the l-nitrogen and Z-carbon atoms will be a hydrogen atom. For purposes of the present disclosure such compounds are considered as 1,2-substituted imidazolines.

The 1,2-substituted' imidazolines are well known and may be prepared by several techniques. A convenient method of preparing them is to react an organic carboxylic acid with ethylenediamine, a polyethylenepolyamine or a hydroxyalkylethylenepolyamine at a temperature sufficient to involve ring closure. In preparing the preferred compositions of the invention the starting organic carboxylic acid is usually a fatty acid containing at least 12 carbon atoms and the starting amine either a polyethylenepolyamine or a hydroxyalkylethylenepolyamine.

Examples of starting saturated fatty acids that may be used in the preparation of the 1,2-substituted imidazolines are: hexanoic, octanoic, decanoic, dodecanoic, tetradecanoic, hexadecanoic, octadecanoic, eicosano-ic, docosanoic and tetracosanoic acids. Several illustrative unsaturated fatty acids useful as starting ingredients are dodecenoic, tetradecenoic, hexadecenoic, octadecenoic, eicosenoic, octadecandienoic and 12-hydroxy octadecencic acids. The various fatty acids which occur in natural fats and oils may also be used. Thus, coconut, corn, cotton seed, linseed, palm, soybean, tall and tung oils a well as such fats as lard and tallow may be employed in the preparaticn of the 1,2-substituted imidazolines. A cheap source of usable organic carboxylic acids. are the petroleum derived naphthenic acids. The starting amines that are particularly suited to react with the organic carboxylic acids are such compounds as ethylenediamine, diethylenetriamine, tetraethylenepentamine and aminoethylethanolamine.

The 1,2-substituted imidazolines may be prepared by any of the several methods described in the article The Chemistry of the Z-Imidazolines and Imidazolidines by R. J. Ferni et al., 54 Chemical Reviews (1954). The 1,(2-hydroxyalkyl) and 1,(2-aminoalkyl) imidazolines conveniently may be prepared by using the general pro cedures set forth in Wilson, U. S. Patents 2,267,965 and 2,355,837.

Examples of specific 1,2-substituted imidazolines contemplated within the scope of the invention are set forth below in Table I.

Table I Identification 1,2-Substituted Imidazoline 1-octyl-2-heptadecyl imidazoline.

2-heptadecyl lmidazoline.

2-heptadecenyl imldazoline.

. Loctadecenyl-Z-mcthyl lmidazoline.

bils aiin ino [1-(Z-aminoethyl)-2-l.ieptadecenyl imidazoine 1 Formed by reacting two mols of oleic acid with one mol. of tetraethylenepuntamiue.

In addition to using the 1,2-substituted imidazolines as chemical treatments for aqueous coke quenching liquids,

1 the carboxylic acid salts of these compounds form a group .of highly desirable chemicals for use in the practice of the invention. While nearly any organic carboxylic acid 4 salt may be used it is preferable to use the earboxylic acid salts of such 1,2-substituted imidazolines as represented by the formula:

VIII

int i wherein R is a higher aliphatic group containing at least 6 and preferably at least 11 carbon atoms, R, Y and Z are from the group consisting of hydrogen and lower aliphatic groups containing not more than 6 carbon atoms and A is an anion of a carboxylic acid fro-m the group consisting of aliphatic monocarboxylic acids, aliphatic polycarboxylic acids, cycloaliphatic polycarboxylic acids and carbocyclic monocarboxylic acids.

Illustrative of the lower molecular Weight aliphatic monocarboxylic acids that may be used in forming the salts of the 1,2-substituted imidazolines are the following: formic, acetic, propionic, n-butyric, isobutyric, n valeric, caproic, chloroacetic, glycolic, vinyl acetic, lactic, acrylic and thioglycolic acids. Higher molecular weight aliphatic carboxylic acids that may be used are hexanoic, dodecanoic, octadecanoic, docosanoic, octadecenoic, lZ-hydroxyoctadecenoic, octadecadienoic, 9,11,13-octadecatrienoic and other similar saturated and unsaturated fatty acids. 'In addition to the fatty acids per se the naturally occurring fats and oils containing varying amounts of fatty acids such as castor, coconut, corn, linseed, soybean and tall oils as well as lard and tallow fats may be employed with good results being obtained in each case. The aliphatic polycarboxylic acid include such well known acids as malonic, succinic, adipic, pimelic, suberic, azelaic, sebacic, citric, gluconic, lactic, glutaric and tartaric. Particularly useful organic aliphatic dicarboxylic acid salts of 1,2-substituted imidazolines are shown in Sterlin, United States application Serial No. 280,197, filed April 2, 1952, now U. S. Patent No. 2,773,879, the dis closure of which is incorporated herein by reference. The most eminently useful acid of this group is sebacic.

The cycloaliphatic polycarbo-xylic acids are usually prepared by reacting a low molecular weight 1,3-diene with maleic anhydride to form a cyclic dicarboxylic acid. Thus, a typical acid, 4-cyclopentene-1,2-dicarboxylic acid, is prepared by reacting 1,3-butadiene with maleic anhydride.

A preferred class of cycloaliphatic polycarboxylic acids are the polymerized fatty acids which have been described in numerous publications. Perhaps the best description of these materials is givenin Industrial and Engineering Chemistry, 32, p. 802et subs., (1940). These materials are composed primarily of dicarboxylic acids derived from the bimolecular addition of unsaturated fatty acids. The polymers are formed by an olefinic polymerization of fatty acids which contain at least two unsaturated linkages. These acids are available from commercial sources. Typical properties of these materials are given below in Table II.

Unsaponifiahle Matter. Neutralization Equivalent Color. Gardner Iodine Number Moisture Content see er? These commercial acids are not pure, but the dicarboxylate polymers which predominate contain about 34-36 carbon atoms. Composition II is a polymerized acid and is a by-product from the caustic fusion of castor oil in the manufacture of sebacic acid.

The carbocyclic rnonocarboxylic acids include such organic acids as benzoic, 4-chlorobenzoic, salicylic, cinnamic, 3,5-dinitrobenzoic, phenoxy acetic and the petroleum derived naphthenic acids. These acid salts of the preferred l,2-substituted imidazolines are described in detail in Luvisi, U. S. ?atent 2,659,731, the disclosure of which is incorporated herein by reference.

The various salts of the 1,2-substituted imidazolines are prepared by blending the ingredients together until a uniform homogeneous product is produced. In many instances it is necessary to apply heat to the mixture to insure the reaction; The salt formation once' started 'is usually accompanied by a rise in temperature from the heat of the reaction.

Several typical 1,2-substituted imidazoline salts are listed below in Table III.

Table III Ratio of Irnidazoline to Acid sebacic acid citric acid-..

tall oil fatty acids. sebacic acid--- .do Conposition I, Table II. o Couaposition II, Table II u- 0 naphthcnic acid. salicylic acid.- cinnarnic acid. benzoic acid Composition I, Table II..... Composition II, Table IL. l2-hydroxyoctadicanoic acid. acrylic acid thioglycolic acid. scbacic acid salicylic acid Composition I, Table II. bcnzoic acid citric acid-..

hcxanoic acid.. linseed oil acids. scbacic acid--... do.. Composition II, Table IL... salicylic acid The 1,2-substituted imidazolines and their carboxylic acid salts, for the most part, are soluble in water at the concentrations of use herein specified, e. g., at least 2 parts per million up to several hundred parts per million. Due to the fact, however, that the pure products are either viscous liquids or wax like solids it is more convenient to dilute them with a solvent so they may be shipped and used more readily. While the products are soluble in many common organic solvents it is preferred to use petroleum base solvents due to the relative ease of preparing formulations. These solvents are suitable for use when the 1,2-substituted imidazolines are used in aqueous systems because stable, uniform emulsions are easily formed. Since some of the salts of the l,2-substituted imidazolines possess detergent properties, the oil formulations have the advantage of tending to suppress undesirable foaming tendencies.

ASTM

Method Specification Typical Gravity API at 69 11...... D28739 10-12 133 Specific Gravity at 60 F. LOGO-03340...- 0.9738

Gallon Weight, lbs.-....

olor

Corrosion Flash Point, O. O. C. 200 F. Mm-.. Kauri Butanol Value. 96 cc. Mimi... 994cc. Pour Point -40 F Mixed Analine Point. 20 C. Main..- 13.3 0 Percent Aromatics. Min 99.2

Distillation, F-.

A typical l,2substituted imidazoline carboxylic acid salt formulation is demonstrated by the following composition.

Composition XLI Ingredients: Percent by weight Composition XIII, Table III 12.5 Bronoco l-Ii-Sol No. 4A 87.5

The compositions of the invention are effectively employed to prevent corrosion of ferrous metals caused by coke quenching operations by dissolving or dispersing suitable amounts of the 1,2-substituted imidazolines or their salts in the coke quench liquid. It may be convenient in some installations to prepare concentrated solutions for purposes of continuous feedin The exact method of treating the aqueous coke quenching liquids may be accomplished by any of several Well known methods used in treating water with chemicals.

EVALUATION OF THE INVENTION Example To determine the effectiveness of the invention it was decided to test Composition XLI in an actual coke quenching operation; The plant was a typical coke producing system. Excessive corrosive conditions were evidenced in the sides and undercarriage of the quench cars, the steel quench tower, the rails on which the quench cars rode and the surrounding steel equipment. There were 104 quenches made per day with a total volume of water evaporated per quench of 2,500 gallons. The water used as a quench liquid was a blend of ammonia still liquor waste and raw water. A typical analysis of this disclosed the following:

pI-I 8.25 Total ammonia p. p. m- .17 Cyanide Trace Phenol p. p. m- 640 The water was collected from the quenching operation and was recycled.

Two sets of test panels were installed at intervals of two and four months before treatment was started. Based on visual inspection, both sets revealed the corrosion to be so severe that weights were not even determined. The test, which was run for several months, used 50 parts per million of Composition XLI in the quench water. Test panels were installed as the test began. At the end of two months the panels showed a minimum of corrosion. The panels were wire brushed in preparation for weighing. It was observed, however, further cleaning preparatory to weighing would be impossible because of the film that was adhering to the panels surface. When weighed after brushing the panels showed an increase in weight.

While the 1,2-substituted imidazolines and their organic acid salts have been described at length it will be understood that the inorganic acid salts of the 1,2- substituted imidazolines are considered for the present purposes as being equivalents to the 1,2-substituted imidazolines per se Thus, halides, sulfates, carbonates, phosphates, borates, sulfamates and the like of the 1,2- substituted imidazolines are also useful'as treatments'for coke quenching liquids;

The expression non-corrosive as used herein and in the appended claims is meant to include any corrosion inhibition obtained by using the practices of the invention and doesnot necessarily mean complete protection being afforded to the surfaces sought to be protected.

The invention is hereby claimed as follows: f

1. The method of rendering coke quenching operations non-corrosive to ferrous metals which comprises quenching coke with an aqueous liquid containing a corrosion inhibiting amount of a 1,2-substituted imidazoline containing at least one aliphatic group of at least 6 carbon atoms.

2. The method of rendering coke quenching operations non-corrosive to ferrous metals which comprises quenching coke with an aqueous liquid containing a corrosion inhibiting amount of a carboxylic acid salt of a 1,2-

. substituted imidazoline containing at least one aliphatic wherein R is a higher aliphatic group containing at least 11 carbon atoms and R, Y and Z are from the group consisting of hydrogen and lower aliphatic groups containing not more than 6 carbon atoms. I

4. The method of rendering coke quenching operations non-corrosive to ferrous metals which comprises quenching coke with an aqueous liquid containing at least two parts per million of a 1,2-substituted imidazoline from the group consisting of wherein R is a higher aliphatic group containing at least 11 carbon atoms and x is a small whole number not greater than 3.

5. The method of claim 4 wherein the 1,2-substituted imidazoline is 1 (2 hydroxyethyl) 2 heptadecenyl imidazoline.

ing coke with an aqueous liquid containing a corrosion inhibiting amount of a carboxylic acid salt of a 1,2-

substituted imidazoline of the formula wherein R is a higher aliphatic group containing at least 11 carbon atoms, R, Y and Z are from the group consisting of hydrogen and lower aliphatic groups containing not more than 6 carbon atoms and A is an anion of a carboxylic acid from the group consisting of aliphatic monocarboxylic acids, aliphatic polycarboxylic acids, cycloaliphatic polycarboxylic acids and carbocyclic monocarboxylic acids.

8. The method of rendering coke quenching operations non-corrosive to ferrous metals which comprises quenching coke with an aqueous liquid containing at least two parts per million of an aliphatic monocarboxylic acid salt of a 1,2-substituted imidazoline containing at least one aliphatic group of at least 11 carbon atoms.

9. The method of claim 8 wherein the aliphatic monocarboxylic acid salt is a fatty acid salt.

10. The method of claim 8 wherein the 1,2suhstituted imidazoline is 1 (2 hydroxyethyl) 2 heptadecenyl imidazoline.

11. The method of rendering coke quenching operations non-corrosive to ferrous metals which comprises quenching coke with an aqueous liquid containing at least two parts per million of an aliphatic polycarboxylic acid salt of a 1,2-substituted imidazoline containing at least one aliphatic group of at least 11 carbon atoms.

12. The method of claim 11 wherein the aliphatic polycarboxylic acid salt contains at least 10 carbon atoms.

13. The method of claim 11 wherein the 1,2-substituted imidazoline is 1-(2-hydroxyethyl)-2-heptadecenyl imidazoline.

14. The method of claim 11 wherein the aliphatic polycarboxylic acid salt is the sebacic acid salt.

15. The method of claim 11 wherein the aliphatic polycarboxylic acid salt of the 1,2-substituted imidazoline is 1-(2-hydroxyethyl)-2-heptadecenyl imidazoline sebacate.

16. The method of rendering coke quenching operations non-corrosive to ferrous metals which comprises quenching coke with an aqueous liquid containing at least two parts per million of a cycloaliphatic polycarboxylic acid salt of a 1,2-substituted imidazoline containing at least one aliphatic group of at least 11 carbon atoms.

17. The method of claim 16 wherein the cycloaliphatic polycarboxylic acid salt isa polymerized fatty acid salt.

18. The method of claim 17 wherein the polymerized fatty acid is a by-product from the caustic fusion of castor oil in the production of sebacic acid.

19. The method of claim 16 wherein the 1,2-substituted imidazoline is 1-(2-hydroxyethyl)-2-heptadecenyl imidazoline.

20. The method of rendering coke quenching operations non-corrosive to ferrous metals which comprises quenching coke with an aqueous liquid containing at least two parts per million of a carbocyclic monocarboxylic acid salt of a 1,2-substituted imidazoline containing at least one aliphatic group of at least 11 carbon atoms.

21. The method of claim 20 wherein the carbocyclic monocarboxylic acid salt is the salicylic acid salt.

References Cited in the file of this patent UNITED STATES PATENTS Re. 23,227 Blair et a1 May 9, 1950 10 Blair et a1 Apr. 5, 1949 Blair et a1 Apr. 26, 1949 Gross June 3, 1952 OTHER REFERENCES Chemical Abstracts, Vol. 48, Cal. 4412B.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No.'2,865,8l'7 December 23, 1958 Irvin A. Clausen It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column '7, lines, 29, 35, Al, and 58, and column 8, lines 6, 28, 39, 56 and '70, after "coke each occurrence, insert the temperature of which is at least 1000 F.,

Signed and sealed this 23rd day of June 1959.

kSEAL) t'test:

KARL PL AXLINE ROBERT C. WATSON Attesting Oflicer Commissioner of Patents UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 2,865,817 December 23, 1958 Irvin A. Clausen It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction and that the said Letters Patent should read as corrected below. I

Column '7, lines 29, 35, 41, and 58, and column 8, lines 6, 28, 39, 56 and '70, after "coke", each occurrence, insert the temperature of which is at least 1000 F.,

Signed and sealed this 23rd day of June 1959.

gsEAL) ttest:

KARL AXLINE ROBERT C. WATSON Attesting Oflicer Commissioner of Patents 

1. THE METHOD OF RENDERING COKE QUENCHING OPERATIONS NON-CORROSIVE TO FERROUS METALS WHICH COMPRISES QUENCHING COKE WITH AN AQUEOUS LIQUID CONTAINING A CORROSION INHIBITING AMOUNT OF A 1,2-SUBSTITUTED IMIDAZOLINE CONTAINING AT LEAST ONE ALIPHATIC GROUP AT LEAST 6 CARBON ATOMS. 